Surgical stapling apparatus with powered articulation

ABSTRACT

The surgical stapling apparatus includes a handle assembly, an elongated body extending distally from the handle assembly, and an articulation mechanism for articulating a tool assembly. The articulation mechanism includes a first gear rotatably mounted on a transmission shaft and configured to engage a second gear, a clutch interconnecting the second gear and a main shaft; and a yoke shaft coupled to the main shaft and adapted to linearly advance a J-channel, the J-channel operatively connected to an articulation link. A motor assembly may rotate the transmission shaft of the articulation mechanism. Alternatively, the articulation mechanism may include an articulation knob. Users may manually rotate the articulation knob to articulate the tool assembly of the surgical stapling apparatus.

BACKGROUND

1. Technical Field

The present disclosure relates to a surgical stapling apparatus. Moreparticularly, the present disclosure relates to an endoscopic surgicalstapling apparatus that includes a mechanism for articulating a toolassembly.

2. Background of Related Art

Surgical fastening devices, such as surgical stapling apparatuses, arewell known in the art. These devices typically include two elongated jawmembers to capture or clamp tissue. One jaw member carries a staplecartridge that houses a plurality of staples arranged in at least twolateral rows while the other jaw member has an anvil that defines asurface for forming the staple legs as the staples are driven from thestaple cartridge. For the most part, the stapling operation is effectedby cam members that travel longitudinally through the staples cartridge,with the cam members actuating upon staple pushers to sequentially ejectthe staples from the staple cartridge. A knife may travel between thestaple rows to longitudinally cut or open the stapled tissue between therows of staples. Examples of this kind of instrument are disclosed inU.S. Pat. Nos. 3,079,606 and 3,490,675.

U.S. Pat. No. 3,499,591 also discloses a stapling apparatus with a pairrow of staples on each side of the incision. The patent discloses asurgical stapler that has an upper jaw member and a lower jaw member.The upper jaw member includes a disposable cartridge while the lower jawmember contains a disposable anvil having a series of staple-closingdepressions aligned with a plurality of staple-carrying grooves of thecartridge. In operation, a cam member translates through an elongatedguide path between the two sets of staple-carrying grooves. Staple drivemembers are located within the grooves and are positioned in such amanner so as to effect ejection of the staples from the staplecartridge. Other examples of such stapling instruments are disclosed inU.S. Pat. Nos. 4,429,695 and 5,065,929.

Each of the instruments described hereinabove is designed for use inconventional surgical procedures wherein surgeons have direct manualaccess to the operative site. Endoscopic or laparoscopic procedures,however, are performed through a small incision or through a narrowcannula inserted through a small entrance wounds in the skin. To addressthe specific needs of endoscopic or laparoscopic surgical procedures,surgical stapling devices have been developed and are disclosed in, forexample, U.S. Pat. Nos. 5,040,715; 5,312,023; 5,318,221; 5,326,013;5,332,142; and 6,241,139.

Tyco Healthcare Group, LP, the assignee of the present application, hassuccessfully manufactured and marketed endoscopic stapling instruments,such as the Multifire ENDO GIA™ 30, Multifire ENDO GIA™ 60 and MultifireENDO TA™ 30 instruments, for a number of years. An articulatingendoscopic stapler known as the ENDO GIA™ Universal stapler has alsobeen marketed. Typically, these devices include an articulationmechanism having an articulation lever operatively engaged with a cammember having a stepped camming channel. Current stapling instrumentsallow manual operation of the articulation lever. These instruments haveprovided significant clinical benefits. Nonetheless, improvements tothese instruments are still possible.

It would be desirable to provide an improved articulation mechanism fora surgical stapling apparatus. It would also be desirable to provide anarticulation mechanism capable of being operated either manually orelectromechanically.

Accordingly, it is an object of this disclosure to provide an improvedarticulation mechanism that articulates the tool assembly of a surgicalstapling apparatus by electromechanical means. It also the object ofthis disclosure to provide an improved articulation mechanism that willallow a user to articulate with minimal effort and with only one handthe tool assembly of a surgical stapling instrument.

Another object of the disclosure is to provide an articulation mechanismcapable of very accurate and fine position adjustment at a speed thatcan be easily controlled by a variable speed switch.

Still another object of the disclosure is to provide an articulationmechanism with a manual override for additional reliability and safety.

SUMMARY

The present disclosure describes a surgical stapling apparatus having ahandle assembly, an elongated body extending distally from the handleassembly, and an articulation mechanism. The articulation mechanism mayinclude a first gear rotatably mounted on a transmission shaft andconfigured to engage a second gear, a clutch interconnecting the secondgear and a main shaft, and a yoke shaft coupled to the main shaft andadapted to linearly advance a J-channel operatively connected to anarticulation link. The yoke shaft of the surgical stapling apparatus caninclude a pin slidably secured on an elongated slot of the J-channel.The J-channel, in turn, may have a projection extending therefrom.Moreover, an articulation knob operatively connected to the main shaftmay be mounted on the distal end of the handle assembly.

The surgical stapling apparatus may further include a motor assemblyoperatively coupled to the transmission shaft. A battery pack may bepositioned on the proximal end of the handle assembly to power the motorassembly. The stapling apparatus may have a switch mounted on theproximal end of the handle assembly for activating the motor assembly.

A surgeon can articulate the tool assembly of the described surgicalstapling apparatus by rotating the transmission shaft. The transmissionshaft may be rotated electromechanically by activating the motorassembly. Alternatively, a user may manually rotate the transmissionshaft by rotating the articulation knob.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top perspective view of an embodiment of the presentlydisclosed surgical stapling apparatus;

FIG. 2 is a top view of the surgical stapling apparatus shown in FIG. 1;

FIG. 3 is a side view of the surgical stapling apparatus shown in FIGS.1 and 2;

FIG. 4 is an enlarged top perspective view, with parts separated, of theproximal housing portion and mounting assembly of the DLU shown in FIGS.1-3;

FIG. 5 is an enlarged perspective view of the axial drive assembly;

FIG. 6 is an enlarged perspective view of the proximal end of the axialdrive assembly shown in FIG. 5;

FIG. 7 is an enlarged perspective view of the distal end of the axialdrive assembly of the axial drive assembly of FIG. 5;

FIG. 8 is a perspective view with parts separated of the axial driveassembly;

FIG. 9 is an enlarged perspective view of the distal end of theelongated body of the stapling apparatus shown in FIG. 1;

FIG. 9 a is a further enlarged perspective view of the distal end of theelongated body of FIG. 9, shown without the control rod extendingtherethrough;

FIG. 10 is an enlarged perspective view of the mounting assembly of thedisposable loading unit shown in FIGS. 1-3 mounted to a distal endportion of the proximal housing portion;

FIG. 11 is an enlarged perspective view of the proximal housing portionand the mounting assembly of the disposable loading unit shown in FIGS.1-3 with the upper housing half removed;

FIG. 12 is a perspective view of the proximal housing portion and themounting assembly of the disposable loading unit shown in FIGS. 1-3 withthe upper housing half removed;

FIG. 13 is a perspective view of a handle assembly according to anembodiment of the presently disclosed surgical stapling apparatus;

FIG. 14 is a perspective view of a portion of a handle assemblyaccording to an embodiment of the presently disclosed surgical staplingapparatus;

FIG. 15 is a perspective view of an articulation mechanism according toan embodiment of the presently disclosed surgical stapling apparatus;

FIG. 16 is a perspective view of an articulation mechanism according toan embodiment of the presently disclosed surgical stapling apparatus;

FIG. 17 is a perspective view of an articulation mechanism according toan embodiment of the presently disclosed surgical stapling apparatus;and

FIG. 18 is a cross-sectional view of an articulation mechanism accordingto an embodiment of the presently disclosed surgical stapling apparatus.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The embodiments of the present disclosure will now be described indetail with reference to the drawings, in which like reference numeralsdesignate identical or corresponding elements in each of the severalviews.

In the drawings and the description that follows, the term “proximal”,as is traditional, will refer to the end of the stapling apparatus whichis closest to the operator, while the term “distal” will refer to theend of the apparatus which is furthest from the operator. Terms such as“above,” “below,” “forward,” “rearward,” etc. are simply used forconvenience of description.

FIGS. 1-3 show a surgical stapling apparatus, generally referred to as10. In the interest of brevity, this disclosure will focus primarily onsystems, methods and structures for articulating a tool assembly ofsurgical stapling apparatus 10. A detailed description of surgicalstapling apparatus 10 is disclosed in U.S. Pat. No. 6,953,139, theentire disclosure of which is hereby incorporated by reference. Althoughthe present disclosure is presented in the context of surgical staplingapparatus 10, the present invention is applicable to any apparatushaving an articulating surgical tool.

Surgical stapling apparatus 10 is an endoscopic apparatus and includes ahandle assembly 12 and an elongated body 14 extending therefrom. Aloading unit which is replaceable and may be disposable, or DLU 16, isreleasably secured to the distal end of elongated body 14. While thedrawings illustrate a DLU 16, it is understood and within the scope ofthe present disclosure that a single loading unit (SULU) or other endeffector can equally be used in cooperation with surgical staplingapparatus 10. DLU 16 includes a tool assembly 17 having a cartridgeassembly 18 housing a plurality of surgical staples and an anvilassembly 20 movably secured in relation to cartridge assembly 18. Asseen in the FIGS. 1-3, DLU 16 is configured to apply linear rows ofstaples. DLUs for applying any number of rows of staples, having staplepockets arranged in various patterns or DLUs and end effectors havingvarious lengths, e.g., 30, 45 mm, or 60 mm, are also envisioned. U.S.Pat. No. 6,953,139, the disclosure of which is hereby incorporated byreference herein, includes a detailed discussion of various kinds ofDLUs. A loading unit having various surgical end effectors may be used,including linear stapling tool assemblies. The linear stapling toolassemblies can include predetermined staple sizes and staple linelengths in various sizes and configurations. The stapling toolassemblies include circular, linear and other shapes.

With reference to FIG. 4, DLU 16 includes a mounting assembly 202.Mounting assembly 202 includes an upper and a lower mounting portion236, 238, respectively. A centrally located pivot member 244 extendsfrom each of upper and lower mounting portions 236, 238 via a pair ofcoupling members 246. Coupling members 246 each include an interlockingproximal portion 248 configured to be received in grooves 290 formed inthe proximal end of upper and lower housing halves 250, 252 to retainmounting assembly 202 and upper and lower housing halves 250, 252 in alongitudinally fixed position in relation to each other.

Upper housing half 250 and lower housing half 252 are contained withinan outer sleeve, shell or casing 251. The proximal end of upper housinghalf 250 includes an insertion tip 193 extending proximally therefrom.Insertion tip 193 includes engagement nubs 254, preferably a pair ofdiametrically opposed engagement nubs 254, extending radially outwardlytherefrom, for releasably engaging the distal end of body 14. Nubs 254form a bayonet-type coupling with the distal end of body 14. Housinghalves 252 and 252 define a channel 253 for slidably receiving axialdrive assembly 212 therein. A second articulation link 256 isdimensioned to be slidably positioned within a slot 402 formed in upperand lower housing halves 250, 252. A pair of blow out plate assemblies255 are positioned adjacent the distal end of housing portion 200adjacent the distal end of axial drive assembly 212 to prevent outwardbuckling and bulging of drive assembly 212 during articulation andfiring of surgical stapling apparatus 10. For a detailed discussion ofthe structure and operation of blow out plate assemblies 255, referenceis made to International Application Serial No. PCT/US02/32031, filed onOct. 4, 2002, entitled “Surgical Stapling Device”, the entire contentsof which are herein incorporated by reference.

With reference to FIGS. 4-8, axial drive assembly 212 includes anelongated drive beam 266 including a distal working head 268 and aproximal engagement section 270. Drive beam 266 may be constructed froma single sheet of material or, preferably, multiple stacked sheets, asshown in FIG. 1. Engagement section 270 includes a pair of resilientengagement fingers 270 a and 270 b which are dimensioned and configuredto mountingly engage a pair of corresponding retention slots 272 a and272 b formed in drive member 272. Drive member 272 includes a proximalporthole 274 configured to receive distal end 276 of a drive member,e.g., drive rod or control rod 52 (FIG. 9) when the proximal end of DLU16 is being engaged with elongated body 14 of surgical staplingapparatus 10. Control rod 52 functions to impart axial movement of driveassembly 212 from handle assembly 12.

In one embodiment, optionally, a locking member may be supported onengagement section 270 of axial drive assembly 212. In operation, whenaxial drive assembly 212 is actuated, by applying a predetermined forceto movable handle member 24 to advance axial drive assembly 212distally, the locking member provides an audible and tactile indicationthat surgical stapling apparatus 10 has been actuated. For a detaileddiscussion of the structure and operation of the locking member,reference is made to the aforementioned International Application SerialNo. PCT/US02/32031, the disclosure of which is hereby incorporated byreference herein. The locking member may also prevent inadvertentpartial actuation of DLU 16, such as during shipping, by locking axialdrive assembly 212 at a fixed position within DLU 16 until apredetermined axial force has been applied to axial drive assembly 212.

Handle assembly 12 includes a stationary handle member 22, a movablehandle member 24, and a barrel portion 26. A rotatable member 28 may bemounted on the distal end of barrel portion 26 to facilitate rotation ofelongated body 14 with respect to handle assembly 12. Two retractionknobs 32 are movably positioned along barrel portion 26 to returnsurgical stapling apparatus 10 to a retracted position. An articulationknob 13 is mounted on the distal end of barrel portion 26 such as onrotatable knob 28 to facilitate articulation of tool assembly 17. Theoperation of the articulation knob 28 and its operative structure is setforth in detail in U.S. patent application Ser. No. 11/544,203, thecontents of which are hereby incorporated herein by reference.

Referring to FIGS. 10-12, second articulation link 256 includes at leastone elongated metallic plate. Two or more metallic plates may be stackedto form link 256. The proximal end of second articulation link 256includes a hook portion 258 configured to engage a first articulationlink, which extends through the elongated body 14, and the distal end ofthe second articulation link 256 includes a loop 260 dimensioned toengage a projection 262 formed on mounting assembly 202. Projection 262is laterally offset from pivot member 244 such that linear movement ofsecond articulation link 256 causes mounting assembly 202 to pivot aboutpivot members 244 to articulate tool assembly 17.

Referring now to FIGS. 13 and 14, surgical apparatus 10 also includes anarticulation actuation mechanism 1. Articulation actuation mechanism 1includes an articulation knob 13 mounted adjacent to rotatable knob 28,a motor assembly 5 and a switch 3, which may be positioned on top of thehandle assembly 12. Switch 3 activates and controls articulationmechanism 1 and is configured to be reached from both sides of surgicalstapling apparatus 10. A battery pack 4 is situated at the handleassembly 12 for supplying power to articulation mechanism 1. It isenvisioned that articulation mechanism 1 may be powered by a suitableexternal energy source.

With reference to FIGS. 15 and 16, motor assembly 5 is supported withinrotatable knob 28 and is operatively connected to a rotatingtransmission shaft 7. A first gear 8 a is mounted on transmission shaft7 so that at least a portion of first gear 8 a surrounds transmissionshaft 7. First gear 8 a has at least one tooth and, desirably, aplurality of teeth. A second gear 8 b is configured to engage first gear8 a and thereby reduce the rotational speed produced by motor assembly5. It is contemplated that any suitable speed reducing means known inthe art may be employed with the articulation mechanism 1 in lieu ofgears 8 a, 8 b. Second gear 8 b is connected to a main shaft 11 by aslip clutch 9 such that rotation of second gear 8 b will causecorresponding rotation of main shaft 11. Slip clutch 9 includes a firstdisk having teeth or grooves and a second disc having teeth or grooves.A spring 19 biases slip clutch 9 upwardly. As seen in FIG. 16,articulation mechanism 1 may include an articulation knob 13 mounted tomain shaft 11. Articulation knob 13 is accessible to the user and can bemanipulated to manually articulate tool assembly 17, or it may serve asan articulation position indicator.

Referring to FIG. 17, main shaft 11 is slidedably attached to a yokeshaft 10 a to allow manual operation of the articulation mechanism 1, aswell as to avoid overloading the motor assembly 5. Yoke shaft 10 aincludes a pin 16 operatively arranged with a J-channel 15. J-channel 15includes a slot 15 a for receiving the pin 16 and a projection 15 b. Pin16 is movably positioned within elongated slot 15 a so that the positionof pin 16 in slot 15 a changes as yoke shaft 10 a rotates with mainshaft 11. Projection 15 b is coupled to the first articulation link.More than one articulation actuation mechanism may be provided tooperate more than one articulation link.

With reference to FIG. 18, in one embodiment, slip clutch 9 includes ashaft 10 a having a pin 2. Pin 2 is slidably received in a slot 6defined in main shaft 11. When the motor drives worm gear 8 a, mainshaft 11 is rotated, transferring the rotation to shaft 10 a. When theclutch 9 slips (at the teeth), main shaft 11 moves upwardly, in thedirection indicated by arrow “A,” with respect to shaft 10. This allowsmanual operation of knob 13 and also prevents overloading of the motorassembly 5.

In a further embodiment, yoke shaft 10 a is attached to, or integralwith, second gear 8 b. To avoid overloading motor assembly 5, a currentsensor is used to shut down motor assembly 5 when the motor assembly 5current reaches a predetermined limit or threshold.

In operation, when motor assembly 5 rotates transmission shaft 7, firstgear 8 a rotates and causes the rotation of second gear 8 b. Therotation speed supplied by motor assembly 5 is reduced by theinteraction of first and second gears 8 a, 8 b. Slip clutch 9 transfersthe rotation of second gear 8 a to main shaft 11. Main shaft 11, inturn, transfers its rotation to yoke shaft 10 a. As yoke shaft 10 arotates, pin 16 moves within elongated slot 15 a. The movement of pin 16causes corresponding linear translation of J-channel 15 to advance thearticulation link. The first articulation link moves axially incombination with the other structural elements discussed above toarticulate tool assembly 17. When the limit of articulation is reached,or when a predetermined force is otherwise reached, slip clutch 9 willdisengage, thus preventing a sudden stop of motor assembly 5. Thedisengagement of slip clutch 9 will produce an audible click to alertthe operator that the articulation limit has been reached.

Alternatively, a user may articulate tool assembly 17 manually. Asurgeon may manually rotate articulation knob 13. As articulation knob13 rotates, slip clutch 9 disengages to prevent back driving motorassembly 5, and main shaft 11 moves upwardly with respect to yoke shaft10 a. The rotation of articulation knob 13 will also cause thecorresponding rotation of the main shaft 11. Yoke shaft 10 a rotates inresponse to the rotation of main shaft 11 to move pin 16. The motion ofpin 16 along the length of elongated slot 15 a causes the linearmovement of J-channel 15. The translation of J-channel 15 advances thearticulation link to articulate tool assembly 17. The connectionsbetween the switch 3 and power source 4 on the one hand, and the motorassembly 5 and gears 8 a, 8 b, J-channel 15, on the other, accommodaterotation of rotatable knob 28. By way of example, a circular slidingcontact may be provided between battery pack 4 and switch 3 in thehandle assembly 12 and the motor assembly 5 in the rotatable knob 28. Inalternative embodiments, the knob 28 is omitted and the body 14 isfixed.

It will be understood that various modification may be made to theembodiments disclosed herein. Therefore, the above description shouldnot be construed as limiting, but merely exemplifications ofembodiments. For instance, the described surgical stapling apparatus 10may be utilized in combination with a servomotor, position sensor, slidering, electric brakes and electronic controls to add functions such aspositioning articulation knob to its initial position, sensing limits ofarticulation with an automatic stop, among others. Those skilled in theart will envision other modification within the scope and spirit of theclaims appended hereto.

1. A surgical stapling apparatus comprising: a handle assembly; anelongated body extending distally from the handle assembly; anarticulation mechanism including: a first gear rotatably mounted on atransmission shaft and configured to engage a second gear; a clutchinterconnecting the second gear and a main shaft; and a yoke shaftcoupled to the main shaft and adapted to linearly advance a J-channel,the J-channel operatively connected to an articulation link.
 2. Thesurgical stapling apparatus according to claim 1 further comprising amotor assembly operatively coupled to the transmission shaft.
 3. Thesurgical stapling apparatus according to claim 2 further comprising abattery pack positioned on the handle assembly and connected to powerthe motor assembly.
 4. The surgical stapling apparatus according toclaim 2 further comprising a switch mounted on the handle assembly foractivating the motor assembly.
 5. The surgical stapling apparatusaccording to claim 1, wherein the yoke shaft includes a pin slidablysecured on an elongated slot of the J-channel.
 6. The surgical apparatusaccording to claim 1, wherein the J-channel includes a projectionextending therefrom.
 7. The surgical apparatus according to claim 1further comprising an articulation knob mounted on the handle assemblyand operatively connected to the main shaft.
 8. A surgical staplingapparatus comprising: a handle assembly; an elongated body extendingdistally from the handle assembly; an articulation mechanism including:a motor assembly operatively coupled to a transmission shaft; and afirst gear rotatably mounted on the transmission shaft and configured toengage a second gear; a clutch interconnecting the second gear and amain shaft; a yoke shaft coupled to the main shaft and adapted tolinearly advance a J-channel.
 9. The surgical stapling apparatusaccording to claim 8 further comprising a battery pack positioned on thehandle assembly and electrically linked to the motor assembly.
 10. Thesurgical stapling apparatus according to claim 8 further comprising aswitch mounted on the handle assembly for activating and controlling themotor assembly.
 11. The surgical stapling apparatus according to claim8, wherein the yoke shaft includes a pin slidably secured on anelongated slot of the J-channel.
 12. The surgical stapling apparatusaccording to claim 8, wherein the J-channel includes a projectionextending therefrom.
 13. The surgical stapling apparatus according toclaim 8 further comprising an articulation knob mounted on the handleassembly and operatively connected to the main shaft.
 14. The method ofarticulating a tool assembly of a surgical stapling apparatus comprisingthe steps of: providing an articulation mechanism including: a firstgear rotatably mounted on a transmission shaft and configured to engagea second gear; a clutch interconnecting the second gear and a mainshaft; a yoke shaft coupled to the main shaft and adapted to linearlyadvance a J-channel; and rotating the transmission shaft to articulatethe tool assembly.
 15. The method of articulating a tool assembly of asurgical stapling apparatus according to claim 14, wherein the step ofrotating the transmission shaft is performed electromechanically. 16.The method of articulating a tool assembly of a surgical staplingapparatus comprising the steps of: providing an articulation mechanismincluding: a first gear rotatably mounted on a transmission shaft andconfigured to engage a second gear; a clutch interconnecting the secondgear and a main shaft; a yoke shaft coupled to the main shaft andadapted to linearly advance a J-channel; and rotating the main shaft toarticulate the tool assembly.
 17. The method of articulating a toolassembly of surgical stapling apparatus according to claim 15, whereinthe step of rotating the main shaft is performed manually.